Foot panel adjustment for hospital bed



June 10; 1958 I Mcc L 2,837,751

FOOT PANEL ADJUSTMENT FOR HOSPITAL BED v 2 Sheets-Shee 1 51/5240 au a/14L v ///5 ATTORNEY June 10, 1958 V s; M. MQCALL 2,337,751

FOOT PANEL ADJUSTMENT FOR HOSPITAL BED I Filed May 19, 1954 2 Sheets-Shan 2 III "N" a U Q! N QM MN J w. I I I i l LT: nlnnunuwl llnck Q L: H l l rl l l h l l l I l W. m m

M Wm United States Pate tit" Sherad M. McCall, Pittsburgh, Pa., assignor to Rosalie G. Silbaugh, Uniontown, Pa.

Application May 19, 1954, Serial No. 430,895

12 Claims. (Cl. -80) T his invention relates to hospital beds. More particularly the invention relates to hospital beds having adjustable panels for the knees and feet to adjust them into ditferent angular positions to obtain desired positions for treating conditions of blood circulation or other ailments and to otbain comfortable positions for a patient on the bed.

In the conventional hospital bed the head and knee panels are adjustable to raise the head and knees, the knee panel is pivotally connected to the foot panel, and as the knees are raised, the heels of the feet move along the bed side rails but are not raised. Usually there is no independent up and down adjustment of the foot panel. Such an arrangement of panels is not desirable to obtain the most advantageous positions of the feet for treating different kinds of ailments.

In the use of adjustable hosiptal beds, it is desirable to have bed adjusting panels which maybe operated by a mechanism that may be operated by a patient on the bed to avoid the necessity of calling a nurse to get the bed adjusted. i

,The adjustment of the bed panels should be slow, steady and quiet and dependable.

. The primary object of the present invention is to pro vide a bed with adjustable panels in its deck by which the knee and foot panels may be individually raised and lowered and may be limited 'to adjustment to assume predetermined angular relations to one another.

Another object of the invention is to provide adjustable panels for a bed which are simple in construction, dependable in operation, and easy to operate.

- With these and other objects and features in view, the invention consists in the adjustable panel hospital bedas hereinafter illustrated and described and particularly defined in the appended claims. 1

r The various features of the invention are'illustrated in the accompanying drawings, in which: i

Fig. lis a view in side elevation of the knee and foot panels of a hospital bed embodying the mechanismfor adjusting. the knee and foot panels of the bed;

:Fig. is a plan view of the knee and foot panel adjusting'rnechanism shown inFigil; V

'Fig. .3 is an end elevation view of the knee. and foot adjusting mechanism taken on the line III-III of Fig. 2;

Fig. 4 is a vertical sectional view of the knee and foot adjusting mechanism taken on the line IV-IV of Fig. 2;

' panel is'independently adjustable (not shown) and is important for adjusting the head of a convalescing patient who wishes to assume a sitting position. It is also important to have the knee and foot panels adjustable in order to hold the feet at an elevated position above the head while the patient is lying on his back While sleeping or while overcoming or treating an ailment. In order to obtain the proper adjustment of the panels for people with different weights, length of legs and body build, it is necessary to have positive adjustability of both the knee and foot panels and provide a coordinated adjustment of these panels to avoid injury to the adjusting mechanism. Further special adjustments are required for treatingdifferent ailments and to make the patient comfortable.

Referring to Figs. 1 and 2, the knee and foot portion of the bed is shown, which contains the knee and foot Fig. 8 is an electrical wiring diagram for operating the I motor and control valves for the hydraulic cylinders,

The present invention is used with a hospital bed-which has adjustable head, knee andfoot panels. The head panels. The knee panel 10 is pivotally connected to a fixed panel 11 mounted on the side rails 12 (Fig. 4) which are connected to the frame of the bed, said frame being supported by a bed foot column 13. The front end of the knee panel 10 has a horizontal pivotal connection 14 with the fixed panel, and the rear end of the knee panel has a horizontal pivotal connection 15 with the front end of a foot panel 16. The side rails 12 are connected by means of angle bars '17 (Figsl and 3) which are mounted at the foot and head of the bed to make a unit frame structure.

To adjust the knee panel, a hydraulically-operated cylinder 18 is pivotally connected at one end to a bracket 19 attached to the bed frame and has a piston rod 20 the knee panel about its horizontal pivots 14. 1

The foot panel is raised and lowered by means of an operating cradle 26 shown particularly in Fig. 5. This. cradle is a unit structure preferably made of tubular steel members which has a lower section 27 containing a pivot rod 28, said rod being pivoted in downwardly-extending arms 29 (Fig. 1) attached to the bottom of the rnid position of the bed frame. From the lower Section 27 substantially horizontal rods 27? extend rearwardly to inclined members 30 connected between the members 27 and upper guide rods 31. The rods 30 and 31 are reinforced by braces 30. The opposite sides of the cradle are connected'by cross braces 31', to make a rigid unit structure. The rear end of the guide rods 31 are con.- nected and rest upon the cross bars 17 in the normal position of the bed. At such time the guide rods 31 are in a horizontal position. Rollers 32 (Fig. 3) are attached to a cross bar 33 of the foot panel 16 (Fig. l), and nornially bear against the guide rods 31 so that as the cradle is oscillated about its pivotal rod 28, the guide rolls 32 move along the rods 31. V I

.The surfaces of the panels 1% and 16 are covered by a wire chain sheet which is connected to the panels by springs as illustrated at A in Fig. 2. Preferably a sponge rubber mattressis used upon the chain sheet which is flexible and will readily assume the angular contour of the adjusted panels.

To operate the cradle for raising and lowering the foot I section, a hydraulic cylinder 34 (Figs. 1 and 2) is con- 'nected' at its front end to the head portion of the bed frame (not shown), and a piston rod 35 in the cylinder 34 is adjustably connected with an axle 36 having trolley wheels 37 (Fig. 4) which ride on tracks 38. The tracks 1 38 are supported in fixed position in the bed frame with theirfront ends secured to hangers 38" that are attached 3 to and extend downwardly fromthe frame angle iron 17, and their rear ends are secured to hangers 36' supported upon shaft 22 (Figs. 2 and 4). As the trolley rolls are moved along the track 33, the trolley rolls 38' rotatably mounted at the ends of axle 36 engage the inclined memhere 39 of the cradle and act to elevate the cradle for adjusting the foot panel.

The arrangement of the hydraulic cylinders 18 and 34 with the fluid circulating and controlling mechanism therefor'is illustrated more particularly in Fig. 7. The cylin ders are double-acting and have tubular connections 39 and 40 at the ends thereof. The connection 39 is supplying pressure fluid to the front end of the cylinder 18 while the connection 40 is permitting the withdrawal of fluid behind the piston to return to a sump. The pressure fluid is provided by means of a pump 41 which is driven by an electrically-operated motor 42 directly connected with the pump. The pressure fluid flows through a supply line 43 which is common to all supply lines for cylinders 18 and 34. A check valve 44 is mounted in each of the supply lines and is so arranged that after pressure fluid passes the check valve it may not return to the supply line 43. These cylinders will remain in the position of adjustment obtained by the fluid supply to the cylinder. The diagram of Fig. 7 shows pressure fluid being supplied to cylinder 18 to raise the knee panel. This diagram also shows cylinder 34 as inactive in a position which results when electrically operated solenoid valves 45 and 46 are disconnected from electrical power, and springs 47 set the valves so that both ends of cylinder 34 are connected to supply line 43, and check valves 44 lock the cylinder piston in the position it has when the power is cut off. The flow of fluid through the cylinders is controlled by the three-Way valves 45 and 46. The position of the valves 45 for the upward movement of the panel is such that pressure fluid is supplied to the front end of the cylinder, while exhaust fluid is removed from the opposite end of the cylinder. For the downward movement of panel 10 the valve 46 is set to supply pressure fluid to the rear end of the cylinder and exhaust fluid from the front end of the cylinder through valve 45. The neutral position of the valves 45 and 46 is shown in Fig. 7 with reference to cylinder 34. The valves are always moved into neutral position by springs 47 when the electrical power is cut off from the valve operating solenoids. Since both lines 39 and 40 of a cylinder are connected to the pressure supply lines, with the valves 45 and 46 in neutral position only one of the valves 45 or 46 needs to be shifted to connect the cylinder which is to be operated to the return line to a sump when obtaining the desired up or down movement of a panel. All of the valves 45 and 46 have a channel by which the valve may be connected with a return line 48 which leads to a sump 49. The fluid for operation of the cylinders is preferably a high flash point oil. This oil is drawn from the sump 49 by the pump 41 through a filter 54 to prevent dirt from getting into the hydraulic system.

The cylinders preferably have a length which determines the length of stroke required in order to limit the upward and downward movement of the panels. Preferably a spring is mounted at each end of the cylinder, and when the piston 55 moves against a spring 56, the pressure in the supply line 43 will be relieved by a relief valve 58 which will permit the. fluid supplied by the pump to pass through the valve 58 to a line 59 to the line 48 to be retu'rned'to the sump. With this construction the up and down movements of the panels is self-limited I by the stroke of the piston within the cylinder.

In Fig. 8 is shown the conventional wiring diagram for controlling the operation of the motor 42and valves 45 and 46. The electrical circuits are controlled by three position'switches, one'switch-being used for operating each hydraulic cylinder. The switches are normally held in a" neutral position by means of spring. plates 60. When switch 61 is operated, contacts 62-62 are made to connect;

circuit lines 63 and 64 through relay 65 to terminals of the powercircuit66. Therelay 65 willclose switch 67 to start motor 42, and after switch 67 is closed current will flow through lines 68 and 68' through solenoid 69 to set valve 46 in position to exhaust fluid from the rear of the cylinder 18 to the sump. With valve 45 in neutral position and valve 46 in position to exhaust fluid, the piston will be moved to give an upward motion to panel 10. If a down operation is desired, a switch 61' will close contacts 71 and 71 to first start the motor through the relay 6S, and then connect a solenoid 70 to operate valve 45 to exhaust fluid from the front end of the cylinder to the sump. The connections just described with reference to switch 61'and 61' for operating the knee panel piston are the same for switches 72 and 72 which control the operation of the foot panel piston of cylinder 34.

As shown in Fig. 1, the knee panel 10 and foot panel 16 are in an elevated dot and dash line position to form a straight angle. This relation of the panels is-preferably a limiting angle because it is not desired to raise the foot panel higher than that shown in Fig. 1. Therefore the knee panel should not be lowered while the foot panel is in the position-shown in- Fig. 1. Accordingly a limiting switch is placed in the electrical circuit for operating the knee panel to prevent it from being lowered while the foot panel is in the position shown in Fig. 1. To accomplish this a cam 73 is attached to the axle 36 (Fig. 6)

and moves longitudinally of the bed, as the axle and trolley wheel 37 are moved. An inclined face 74 on the cam 73 is arranged to make contact with electrical circuit switches 75 and 76 (Fig. 2). The switch 75 is shown in Fig. 8 as in the circuit controlling downward movement ofthe hydraulic cylinder 18. So long as the angular relation between the surface of the panels 10 and 16 is more than a straight angle, as the panels move from the horizontal'surface of the bed to the elevated position of Fig.- l,'the knee panel may be moved up and down provided the foot'panel isin a position where it does notmake a straight angle with the knee panel. The cam surface 74 remains out of 'contactwith the switches 75 and 76 to hold the electrical circuit closed for normal operation of the panels as long as the angle between the panel surfaces is more than a straight angle. If the axle 36 is moved to the end of its line of travel to the place that the foOt'se'ctiQn is in elevated position and the knee section is also moved into a position to place the knee section at the upper limit of its movement, then rollers on switches 75 and'76'will contact the cam surface 74 at the positions shown in dot and dash lines in Fig. 6 and the circuit will be broken so that the knee section may not be operated;

The relative movement of the cam 74 and the switch 75 in order to carryout the preferred operation of the panels is maintained by means of a cam 77 mountedontions of the panels other than in the straight line positionshownin Fig. 1. The second switch 76 mounted on the lever 78 controls the'operation of the foot panel during the upward movement. of the panel to prevent the driving mechanism from moving the foot panel into a position that would make anangle of the'panels above the position shown Fig.1 that is less than a straight angle. The. switches 75 and 76 are both mounted onvthe lever 74 and:

the-rollers ofthe switches-may be'adjusted so that both switcheswilli'be opened when the panels are moved into" thecritieal angle- When. the panelsareat thecriticajl angle "thefoot panel-may be moved down to closeswitches 75 and 76 to place the panel in position for further dju t e j,

)With the construction outlined above, the knee and foot panels maybeindependently moved and will have a limiting action only on the down movement of the knee panel and on the up movement of the foot panel. Both panels are self-limiting for both the extreme up and extreme down positions. Each panel is operated by a single switch which controls thesupply of pressure fluid to the operating hydraulic cylinders and also controls the valves for obtaining an up or down movement. Preferably the switches for controlling the operation are located at the side of the bed whereby the patient may operate the panels while on the bed. The pump with the control valves and the supply' and return lines for the hydraulic fluid are preferably mounted as a unit under the bed to make a construction which is neat and inconspicuous in appearance.

The preferred form of the invention having been thus described, what is claimed as new is:

1. In a hospital bed, a bed frame, adjustable knee and foot panels pivotally connected together with the front end of the knee panel pivotally connected to a fixed mid portion of the bed frame, a unit cradle structure having its front end pivotally mounted below the panels to the bed frame, said cradle having guide rods positioned adjacent opposite sides of the foot panel to receive flanged rollers secured to the bottom of the rear end of the foot panel, the intermediate portion end of the cradle being supported by a trolley which is movable along rails secured in the bed frame adjacent the cradle rods and means to move the trolley along the rails to oscillate the cradle about the pivotal connection to raise and lower the foot panel.

2. The foot panel adjusting mechanism as defined in claim 1 in which the cradle has an inclined cam surface against which lifting rollers on the trolley are moved in a fixed line extending at an acute angle to the cam surface to swing the foot panel about its pivotal connection to the knee panel.

3. The foot panel adjusting mechanism as defined in claim 1, in which the cradle has cam surfaces adjacent the rails which are arranged at an acute .angle to'the rails, and rollers on the trolley ride along the rails and the cam surfaces as the trolley is moved along the rails to move the cradle and foot panel up and down for desired adjustments.

4. In a hospital bed, a bed frame, a movably mounted knee and foot panel pivotally connected together with the front end of the knee panel pivotally connected to the bed frame to oscillate about a horizontal axis, a pressure fluid operated reciprocable piston in a cylinder connected by linkage with the knee panel to raise and lower the knee panel, a unit structure cradle pivotally connected to the mid portion of the frame below the panels, said cradle having guide rods at opposite sides thereof engaging rollers on the bottom of the rear end of the foot panel, a fluiddriven reciprocable piston in a cylinder connected with a trolley moveably mounted on rails secured in the frame below the panels, said trolley having rollers engaging cam faces on the cradle arranged to oscillate the cradle when the piston is reciprocated to adjust the rear end of the foot panel vertically, and electrically controlled fluid circulating means connected to the cylinders to supply pressure fluid to operate the pistons.

5. The hospital bed panel adjusting mechanism as defined in claim 4 in which a cam mounted on and movable with the cradle adjusting device is arranged to contact and hold an electrical limiting switch in the foot panel operating circuit in closing position during the normal oscillation of the cradle, and means operated by a cam connected with the knee panel operating mechanism to open the limiting switch when the knee and foot panels are adjusted into a predetermined angular position to discontinue the adjustment of the panels.

6. The hospital bed panel adjusting mechanism defined in claim 4 in which a pump is connected to the cylinders to supply fluid under pressure for operating the pistons and the pump and the control valves in the fluid flow lines connected to the cylinders are controlled by manually operated switches in an electrical circuit arranged to selectively move the knee and foot panels up and down.

7. Thehospital bed panel adjusting mechanism as defined in claim 5 in which the camconnected on the foot panel adjusting mechanism is moved relatively to the upward movement of the foot panel and the cam for operating the knee panel is shaped to move a lever having an electrical switch thereon to hold a roll on the switch out of contact with the foot panel cam to keep the switch in circuit closing position during the upward movement of the knee panel and to cause the switch roll to open the electrical circuit during the'downward movement of the knee panel if the knee and foot panels are brought into a predetermined angular relation to one another to discontinue the adjustment of the knee panel until the angular relation of the panels has been corrected.

8. The hospital bed adjusting mechanism as defined in claim 7 in which an electrical circuit switch is moved by the knee operating panel cam into contact with the cam on the foot panel operating mechanism to hold the electrical circuit closed, said cam being shaped to allow the foot operating circuit switch to open during the upward movement of the foot panel if the panels are brought into a predetermined angular relation to one another to prevent further operation of the foot panel until the angular position of the panels has been corrected.

9. The bed panel adjusting mechanism defined in claim 6 in which a limiting switch is mounted in the electrical circuit controlling the movement of the knee panel and means movable with the foot panel moving means for stopping the downward movement of the knee and foot panels when the surface of the foot panel reaches a predetermined angle with reference to the surface of the foot panel, and a relief valve in the fluid supply line acting to limit the ultimate upward movement of the knee and foot panels.

10. The bed panel adjusting mechanism defined in claim 9 in which the up and down movement of the knee and foot panels may be effected independently of one another and limiting switches in the electrical circuit of the knee and foot panel electrical operating mechanism are arranged to stop the movement of each of these panels when the surfaces of the knee and foot panels are moved into a predetermined angular relation at any point in the entire range of movement of the panels.

11. The bed panel adjusting mechanism defined in claim 9 in which a limiting switch is arranged in the elec trical circuit to control the downward movement of the knee panel and a limiting switch is arranged in the electrical circuit to control the upward movement of the foot panel, said limiting switches being arranged to limit the movement of the panels if the surface of the panels is moved into a predetermined angular relation to one another.

12. In a hospital bed, a bed frame, adjustable knee and foot panels hingedly connected together with the front end of the knee panel pivotallyconnected to the mid portion of the frame, a cradle having a horizontal pivotal connection to the mid portion of the frame and having guide rods positioned below the panel, rollers at the sides on the bottom of the foot panel engaging the cradle guide rods, a fluid operated reciprocatable piston in a cylinder connected by a linkage to the knee panel, means to supply pressure fluid to the cylinder to raise and lower the knee panel, a vertically inclined rod at each side of the cradle and power operated means movable in engagement with the inclined rods to oscillate the cradle about its horizontal axis for raising and lowering the foot panel.

(References on following page) 

